1. FIELD OF THE INVENTION
This invention relates to sheathing for poles and similar extending members for protecting vehicles when vehicles strike these poles and extending members and more particularly to sheathing which is generally suitable for various extending members having either rectangular or circular cross sections and which may be easily stacked for packaging and shipping prior to use and easily assembled for use.
2. PRIOR ART
It is known in the art to insulate pipe members and other tubular or extending members by wrapping insulating material, such as mineral wool, in sheets around the member to form a lining around the pipe or tube to be insulated and covering the lining by a final wrapping of moisture impermeable material, such as asphalt coated paper, canvass tape, etc. Furthermore, it is also known to form a cylindrical sleeve around pipe members and tubular members from foam plastic which has been divided along a line or lines, whereupon the part cylinder sleeve members obtained thereby can be arranged around the pipe or tube to be insulated and can be secured by means of separate fastening parts or integral fastening parts. The separate fastening parts may comprise an outer wrapping such as asphalt coated paper or canvass tape laid around the outer circumference of the cylinder sleeve.
Thus sheaths were formed of a insulating pipe covering which comprised substantially identical hollow semi-cylindrical sections of a substantially rigid cellular plastic material. The sections were oriented to cooperatively define a hollow cylindrical element having a longitudinal axis. The cylindrical element was adapted for accommodating a pipe therein, with the semi-cylindrical sections in contact with the pipe or tube. Interengagement between undercut tongues and grooves in the sections could connect the sections securely to each other. Such an arrangement was disclosed in U.S. Pat. No. 3,126,035 issued to Espetvedt on Mar. 24, 1964.
However, sheathing for protecting pipe members and similar tubular members of the type taught by Espetvedt was not efficiently stackable for packing and shipping because of the semi-circular shape of the sheathing sections. The outer radius of one section of the semi-cylindrical sheathing did not fit within the inner radius of another section of the semi-cylindrical sheathing, thereby wasting space between sections because the surfaces of adjacent sections during stacking were not in contact with each other. This prevented efficient stacking of the sections for the purpose of packaging and shipping. Additionally, the semi-cylindrical sheathing sections were only adapted for effectively surrounding cylindrical members. Extending members which were not cylindrical, for example I-beams or other types of extending members having rectangular cross sections, required a different kind of sheath. Thus prevented the efficiency which would result from having a single type of sheath for both shapes of extending members, those with rectangular cross sections and both those with circular cross sections.
A method for producing conventional continuous tubular foamed plastic pipe sleeves is taught in U.S. Pat. No. 4,087,501 issued to Moser on May 2, 1978. The semi-cylindrical sleeve sections produced by this method could be joined to surround a pipe member or tubular member.
Protective padding which was flat and easily stackable for efficient packaging, storing, and shipping is taught in Keil, U.S. Pat. No. 3,410,474, issued Nov. 12, 1968. The invention in the art of packaging taught by Keil comprised protective padding assembled from three identical modules to be held together by dove tail tongue and groove joints, each module containing an extending dove tail tongue and a recessed dove tail groove. The extending dove tail tongue of the first module fitted into the recessed dove tail groove of the second module, the dove tail tongue of the second module fitted into the dove tail groove of the third module, and the dove tail tongue of the third module fitted into the dove tail groove of the first module.
Because, all three of the modules taught by Keil were completely flat they could be easily stacked for packaging and shipping. Furthermore, because they were made of a resiliently compressible, shock absorbent material such as polyethelene, when they locked together they formed very effective padding for protecting objects from impact with the protected member. However, the three modules of Keil could only be fitted together to provide protective padding for a single corner of an object and could not be used to form a structure which could surround pole members and tubular members and other extending members to sheath such extending members and to protect vehicles when the vehicles struck the pole members and tubular members.
Both U.S. Pat. No. 3,181,849, issued to Mitchell on May 5, 1965, and U.S. Pat. No. 3,936,040, issued to Wilson on Feb. 3, 1976, taught protective padding which surrounded an extending member such as a pipe member or tubular member for protecting bodies which struck the pipe member or tubular member. The shock absorbing guard of Mitchell was adapted for areas in sports arenas and the like to prevent injuries to people who hit extending tubular members such as the supports for a basketball backboard. The device taught by Wilson required rigid plates to be woven into a molded surface layer of a guard which was planar. The molded guard was then wrapped around a pipe member or tubular member to be protected. The resilient guard of Wilson was bolted onto the extending member.
Therefore it is the object of this invention to provide a sheathing for extending members such as pipe members, tubular members, and members having a rectangular cross section for protecting the sheathed extending members from vehicles when vehicles strike the extending members.
It is a further object of the invention to provide a sheathing for extending members such as pipe members, tubular members and extending members having a rectangular cross section which may be efficiently stacked for packaging and shipping without wasted space between adjacent stacked sheathing sections.
It is a further object of the invention to provide a sheathing for extending members such as pipe members, tubular members and extending members having a rectangular cross section to protect the sheathed extending member when vehicles strike the extending member in which the sheathing is easily assembled for use.
Finally it is an object of the invention to provide a single sheathing for protecting both extending members having a rectangular cross section and extending members having a circular cross section.